Strange and charged particle elliptic flow in Pb+Au collisions at 158 AGeV/c

Abstract

We present $\Lambda$ and $\pi$ elliptic flow measurements from Pb+Au collisions at the highest SPS energy. The data, collected by the CERES experiment which covers $\eta=2.05,2.70$ with full azimuthal coverage and wide $p_{T}$ sensitivity up to 3.5 GeV/c, can be used to test hydrodynamical models and show sensitivity to the EoS. The value of $v_{2}$ as a function of centrality and $p_{T}$ is presented. Values of $v_{2}$ observed by STAR at RHIC are larger by about 1/3. Our measurements are compared to results from other SPS experiments and to hydrodynamical calculations. Huge statistics allows for a precise measurement of the differential pion elliptic flow.